Safety stopping and starting mechanism for printing-machines



3 Sheets-Sheet 1. W. SCQTT.

Patented Apr. 26, 1887..

N. PETERS: PlIvlo-Liihognpher, Washington mc.

(No Model.)

SAFETY STOPPING AND STARTING MECHANISM FOR PRINTING MACHINES.

No. 361,786. I

(No Model.) 3 Sh'eetS Sheet 2.

W. SCOTT.

SAFETY STOPPING AND STARTING MECHANISM FOR PRINTING MACHINES. N0.361,786. Patented Apr. 26, 1887.

I w E- QKQ N a e N 1- T i k T Q E --J duh 56 (No Model.) a Sheets-Sheeta.

W. SCOTT.

SAFETY STOPPING AND'STARTING. MEGHANISMFOR PRINTING MACHINES. No.361,786. Patented'Apr. 26, 1887-.

UNITED STATES PATENT OFFICE.

VVALTER SCOTT, OF PLAINFIELD, NEW JERSEY.

SAFETY STOPPING AND STARTING MECHANISM FOR PRINTING-MACHINES-SPECIPICATION forming part of Letters Patent No. 361,786, dated April26, 1887.

application filed January 21, 1887. Serial No. 224,976. (No model.)

To all whom it ma y concern:

Be it known that LXVALTER SCOTT, of Plainfield, in the county of Unionand State of New Jersey, have invented an Improvement in Safety Stoppingand Starting Mechanism for Printing-Machines, of which the following isa specification.

This invention is especially available with stop cylinder or tworevolution printingpresses; but it may be applied with the stoppingdevices of any printing-press or other machinery where the trip orstopping devices are operated by foot or hand power to disconnect orthrow off the cylinder or other device, and thereby arrest the printingor other operation.

In the drawings, Figure 1 is-an elevation of a portion of aprinting-presswith my improvements applied thereto. Fig. 2 is a partialplan of the shafts and connections, and Fig. 3 is a side elevation ofthe cam and its yielding point. Fig. 4 is a section at the line w x ofFig. 3. Fig. 5 is a section at the line y y, Fig. 3. Fig. 6 is aseparate elevation of the safety-bar and rocking piece. Fig. 7 is a planview of the same; and Fig. Sis a diagram representing the yielding pointof the cam and point of the rockmg piece in contact, showing, also,thedirection of movement as the parts yield and separate.

The bed of the press is shown at A, and the impression-cylinder at B. Gis the startingbar, with teeth at the upper end thereof gearing intoteeth upon the gear-wheel G upon the axis of the impression-cylinder,and there is a locking-bar, D,with a tooth, 2, that passes into thenotch of a block upon the gear 0 to hold the impression-cylinder in theproper fixed position between one impression and the next. Thislocking-bar is supported upon the frame of the machine and raised orlowered by a cam, 8, and rack 4, that receives its motion from thefoot-trip F, or other device usually provided in printing-presses. Ihave shown the foottrip F as connected to the bent lever 6 and aconnecting-rod, 7, to the crank 8 on the shaft 9, that carries thesector or rack 4, so that when the foot is placed upon the trip F thesegmental rack 4. will be moved and the cam 3 partially revolved to holdthe lock-bar D,with its tooth 2, in such a position as to prevent theimpression cylinder being moved. A morev I full description of a deviceof this character will be seen in my Patents Nos. 293,678 and 298,781issued to me.

The crank-shaft of the press is shown at G, and upon this are the camsH, that act upon the rollers I, that are upon arms extending out fromthe startingbar lever 0 so that the starting-bar lever is vibrated bythese cams at the proper time for engaging the teeth upon thestarting-bar with the teeth upon the gearwheel of theimpression-cylinder.

Upon the shaft 9 is a crank, L, to which is connected one end of thesafety-bar K, and this bar K is forked to pass above and below thecrank-shaft G, and upon this crank-shaft Gris a shell or side cam, M,and upon the safety-bar K is a stud, O. The cam M is an arc of acircle,or nearly so, and the stud 0, being within the cam, prevents theshaft 9 being turned by the action of the foot-trip except when the studOis at the opening between the ends of the cam M. These parts haveheretofore been used in printing-presses, but the press is sometimesinjured or broken by the end of the cam M striking upon the stud O, andthis may occur even in cases where the end of the cam is pointed orwedge shaped and where the stud O is also pointed.

My present invention is made for effectually preventing the risk ofinjury to the press under the circumstances before named; and itconsists, first, in combining with the cam and safety-bar a yieldingpointed stud that will cause a separation between such stud and the endof the cam, should the parts accidentally come squarely together, and,second, in a yielding point to the cam that will cause the parts toseparate in case of accidental contact between the cam and the stud.

The rocking piece O"is pivoted at 10 upon the safety-bar K, and there isan elongated hole in the rocking piece, into which the stud 0 passes,and the arm P extends out from the rocking piece 0, and there aresprings Q acting at each side of the arm P and serving to hold the saidarm Pin a central position upon the safety-bar K. These springs may beeither tension or compression springs. Ihave shown them as placedagainst abutments 12 upon arms extending out laterally from thesafety-bar K. It will be now understood that IOC as soon as the ends of.the cam M passout of contact with the rocking piece 0' the springs Qbring the said rocking piece and its arm I? into a central position uponthe safety-bar K,

and if said bar K is moved endwise in either direction at this time theend of the cam M might strike exactly upon the pointed end of therocking piece 0, in which case the said rocking piece Owill swing uponthe pivot 10, compressing one of the springs Q, and in so doing thepoint of the rocking bar will describe an arc of a circle from the pivot10,and thereby carry the point of the rocking piece out of contact withthe point of the cam'and allow said cam M to move the safety-bar K andthe parts connected therewith in either-one direction or the other.

As an additional safeguard, I provide a pivoted end, S, to the cam M,said end S having a projecting pin or bolt, 20, passing through an earupon the disk of the cam M, and having outside of the disk a crank-arm,21, against which a spring, 22, operates to hold the yielding point S ofthe cam in a normal position, and a stop, 24,, limits the movement ofthe cam end S under the expansive action of the spring; but should thepoint of the cam end S strike directly upon the pointed end of therocking piece 0, or upon the stud 0, if that alone be used, then the camend S swings upon its pivot-bolt 20, the spring 22 is partiallycompressed,and the point of the cam end S yields and describes an arc ofa circle from the pivot 20, so that the point of the cam end movesacross the stud or rocking piece and the said stud or rocking piecepasses either at one side or the other of the cam M, and there is nopossibility for the motion being obstructed and the parts broken.-

Upon reference to Fig. Sit will be seen that the are described by thepoint of the yielding stud coincidesmore nearly with the radial linethan does the are described by the yielding point of the cam. For thisreason the two yielding points will separate in describing theirrespective arcs should, they ever come together exactly end to end, andthereby injury will be prevented by the points clearing each other. Thesprings also may be of different strengths.

It will be noticed that the rocking piece 0 is pointed in bothdirections and that two springs Q are employed to bring the partscentral. This is preferable, because it prevents injury to the partswhen the press is being turned back by hand; but the two points to therocking piece are not always necessary, as the force employed in turningthe press backwardly by hand is seldom sufficient to 6o injure any ofthe parts.

It is preferable to locate the pivot of the rocking stud in the positionshown; but the action will be the same if the pivot is toward 7 theshaft instead of away from the same.

The action of the parts will be the same whether my improvements areapplied to a stop-cylinder printing-press, as illustrated in thedrawings, or to a two-revolution printingpress in which the cylinder israised and kept out of contact with the type-bed to prevent animpression being taken, and my improvements may be used whereveravailable.

I claim as my invention- 1. The combination,with the safety-barK and camM in the starting and stopping mechanism, of arocking stud, O, a pivot,10, to connect the same to the safety-bar, an arm extending out from therocking stud, and a spring acting upon the arm to swing the rockingpiece upon its pivot, substantially as and for the purposes set forth.

2. The combination, with the safety-bar K and cam M in the starting andstopping mechanism, of the rocking piece 0, having two pointed ends, thearm P, carrying said rocking piece, the pivot 10, connecting the partsto the bar K, and the springs Q, acting in opposite directions to movethe arm and rocking piece into a central position, substantially as setforth.

3. The'combination, with the safety-bar and its stud in the stoppingmechanism, of the cam M, having a yielding end to the cam,..a pivot uponwhich the yielding cam S swings, and a spring to return the yielding camend to its normal position, substantially as set forth.

4. The combination, with the safety-bar K, of the rocking piece 0, armP, pivot 10, upon which the rocking piece swings, the stud 0 within anelongated holein the rocking piece, the cam M, the yielding cam end S,the pivot 20, the arm 21, and spring 22, substantially as and for thepurposes set forth.

5. The combination, with the cam and a pivoted yielding end to the cam,of a supplybar moving endwise, and a yielding rocking stud upon thesame, the are described by the yielding end of the rocking stud beingdifferent from the are described by the yielding end of the cam, so thatthe two parts separate while moving, substantially as set forth.

Signed by me this 11th day of January, 1887.

VVALTEB SCOTT.

Witnesses:

GEO. T. PINCKNEY, WILLIAM G. Mor'r.

